Datasheet

Chapter 1: The Least You Need to Know about HTML, CSS, and the Web

hosts for your Web site with a little effort. Free Web Hosts maintains a

list of free host providers. Check them out at www.free-webhosts.

com. Chapter 3 shows how to determine your hosting needs and find the

perfect provider.

Anatomy of a URL

The Web is made up of billions of resources, each of them linkable. A

resource’s exact location is the key to linking to it. Without an exact address

(a Uniform Resource Locator, or URL), you can’t use the Address bar in a Web

browser to visit a Web page directly.

URLs are the standard addressing system for Web resources. Each resource

(Web page, site, or individual file) has a unique URL. URLs work a lot like

your postal address. Figure 1-3 identifies the components of a URL.

Protocol

Domain

http://www.domain.com/mainfolder/subfolder/file.html

Path

Filename

Figure 1-3: The components of a URL help it define an exact location for a file

on the Web.

Introducing Internet protocols

Interactions between browsers and servers

are made possible by a set of computer-

communication instructions: Hypertext Transfer

Protocol (HTTP). This protocol defines how

browsers should request Web pages and how

Web servers should respond to those requests.

HTTP isn’t the only protocol at work on the

Internet. The Simple Mail Transfer Protocol

(SMTP) and Post Office Protocol (POP) make

e-mail exchange possible, and the File Transfer

Protocol (FTP) allows you to upload, download,

move, copy, and delete files and folders across

the Internet. The good news is that Web brows-

ers and servers do all the HTTP work for you, so

you only have to put your pages on a server or

type a Web address into a browser.

To see how HTTP works, check out David

Gourley and Brian Totty’s chapter on HTTP

Messages, available through Google book

search with “understanding http transac-

tions” as the search string. Start your search at

http://books.google.com, then scroll

down until you see the link to “HTTP: the defini-

tive guide” and check out Page 80.

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